Mybatis Mapper代理连接数据库 Mybatis通过Mapper代理连接数据库的方法
华农小菜鸡DrLai 人气:0想了解Mybatis通过Mapper代理连接数据库的方法的相关内容吗,华农小菜鸡DrLai在本文为您仔细讲解Mybatis Mapper代理连接数据库的相关知识和一些Code实例,欢迎阅读和指正,我们先划重点:Mybatis,Mapper代理连接数据库,Mybatis,Mapper代理,下面大家一起来学习吧。
1.在数据库中创建表和相应字段,如下图我创建了三个字段分别为fromname,message,toname,类型为varchar
2.创建对应的pojo实体类,注意类型要和数据库创建类型一致,如varchar()对应的是java.lang.String
3.在resource路径下配置config.xml,配置Mybatis的运行环境3306/后面加上自己的数据库schema名字,数据库username和password输入自己的账号和密码,而在下方mapper则是用于注册我们待会要写的xml文件,路径用/ 写上xml的全名称。
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <!--配置Mybatis运行环境--> <environments default="development"><!--default命名--> <environment id="development"><!--和上面的一致--> <transactionManager type="JDBC"></transactionManager><!--事务管理 交给JDBC--> <!-- 数据源 --> <dataSource type="POOLED"> <property name="driver" value="com.mysql.cj.jdbc.Driver"/> <property name="url" value="jdbc:mysql://localhost:3306/bjpower? useUnicode=true&characterEncoding=UTF-8"/> <property name="username" value="root"/> <property name="password" value="xxxx"/> </dataSource> </environment> </environments> <mappers> <!-- <mapper resource="com/yyj/repository/msgdataRepository.xml"></mapper>--> <mapper resource="com/yyj/repository/msgdatanewRepository.xml"></mapper> </mappers> </configuration>
4.自定义接口,在repository包下自定义接口,待会在xml中实现即可
5.在repository中建立对应的xml文件,如我取的名称为MsgdatanewReposiotory,名字可自定义,注意mapper注册和改名字一样即可,然后编写sql语句
statement 的 id 为接⼝中对应的⽅法名
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="com.yyj.repository.MsgdatanewRepository"><!--接口全类名--> <insert id="save1" parameterType="com.yyj.pojo.MessageData"> <!--parameterType为传入的参数类型,是刚刚设置的pojo类--> insert into msgdatanew(fromname,message,toname) values (#{fromName},#{message},#{toName}) </insert> <!--resultType为返回值类型--> <select id="findByName1" parameterType="java.lang.String" resultType="com.yyj.pojo.MessageData"> select * from msgdatanew where toname = #{toName} </select> </mapper>
6.调用测试类即可,注意要添加commit事务才能提交成功,数据库才有变化
package com.yyj.Test; import com.yyj.pojo.MessageData; import com.yyj.repository.MsgdatanewRepository; import org.apache.ibatis.session.SqlSession; import org.apache.ibatis.session.SqlSessionFactory; import org.apache.ibatis.session.SqlSessionFactoryBuilder; import java.io.InputStream; public class Test2 { // public void add(String toName,String message,String fromName){ public static void main(String[] args) { InputStream inputStream = Test2.class.getClassLoader().getResourceAsStream("config.xml"); SqlSessionFactoryBuilder sqlSessionFactoryBuilder = new SqlSessionFactoryBuilder(); SqlSessionFactory sqlSessionFactory = sqlSessionFactoryBuilder.build(inputStream); SqlSession sqlSession = sqlSessionFactory.openSession(); MsgdatanewRepository msgdatanewRepository = sqlSession.getMapper(MsgdatanewRepository.class); MessageData messageData=new MessageData(); messageData.setMessage("nihaoyayay"); messageData.setFromName("lisi"); int save = msgdatanewRepository.save1(messageData); System.out.println(save); sqlSession.commit(); } }
7.效果展示
8.附上pom.xml文件
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.demo</groupId> <artifactId>websocket-chatroom</artifactId> <version>0.0.1-SNAPSHOT</version> <name>websocket-chatroom</name> <description>WebSocket示例工程</description> <properties> <java.version>1.8</java.version> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <spring-boot.version>2.3.7.RELEASE</spring-boot.version> </properties> <dependencies> <!--mybatis--> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>3.4.5</version> </dependency> <!--mysql驱动--> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>8.0.27</version> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-websocket</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-devtools</artifactId> <scope>runtime</scope> <optional>true</optional> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> <exclusions> <exclusion> <groupId>org.junit.vintage</groupId> <artifactId>junit-vintage-engine</artifactId> </exclusion> </exclusions> </dependency> </dependencies> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-dependencies</artifactId> <version>${spring-boot.version}</version> <type>pom</type> <scope>import</scope> </dependency> <!-- <!– ehcache –>--> <!-- <dependency>--> <!-- <groupId>net.sf.ehcache</groupId>--> <!-- <artifactId>ehcache-core</artifactId>--> <!-- <version>2.4.3</version>--> <!-- </dependency> <dependency>--> <!-- <groupId>org.mybatis</groupId>--> <!-- <artifactId>mybatis-ehcache</artifactId>--> <!-- <version>1.0.0</version>--> <!-- </dependency>--> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>3.8.1</version> <configuration> <source>1.8</source> <target>1.8</target> <encoding>UTF-8</encoding> </configuration> </plugin> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <version>2.3.7.RELEASE</version> <configuration> <mainClass>com.yyj.WebsocketChatroomApplication</mainClass> </configuration> <executions> <execution> <id>repackage</id> <goals> <goal>repackage</goal> </goals> </execution> </executions> </plugin> </plugins> <resources> <resource> <directory>src/main/java</directory> <includes> <include>**/*.xml</include> </includes> </resource> </resources> </build> </project>
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